Version 2 Fields

An X.509 version 2 certificate contains the basic fields defined in version 1 and adds the following fields.

Issuer Unique Identifier

Contains a unique value that can be used to make the X.500 name of the CA unambiguous when reused by different entities over time.

---------------------------------------------------------------------
-- Issuer Unique identifier
---------------------------------------------------------------------
issuerUniqueIdentifier ::= [1] IMPLICIT UniqueIdentifier OPTIONAL

UniqueIdentifier ::= BITSTRING

Subject Unique Identifier

Contains a unique value that can be used to make the X.500 name of the certificate subject unambiguous when reused by different entities over time.

---------------------------------------------------------------------
-- Subject Unique identifier
---------------------------------------------------------------------
subjectUniqueIdentifier ::= [2] IMPLICIT UniqueIdentifier OPTIONAL

UniqueIdentifier ::= BITSTRING

Basic Fields

Version 3 Extensions

X.509 Public Key Certificates